On Mon, Nov 16, 2015 at 10:47 PM, Jason Merrill <ja...@redhat.com> wrote: > On 11/16/2015 09:39 PM, David Edelsohn wrote: >> >> The PPC port seems to be bootstrapping again, but I'm not sure why. >> Mike Meissner's patch only should have affected long double. > > >> It's hard to know if there is a latent bug that has gone back into hiding. > > > The problem was twofold: > > 1) VSX_L included IFmode, but VSa didn't, so expanding various patterns over > VSX_L generated an IFmode insn that still had <VSa> scattered around. > Mike's patch fixed this. > > 2) The delayed folding merge changed > > __builtin_constant_p (non-constant-expr && false) > > to be false because the operand is not a C++ constant expression. Previously > we had seen that the IFmode insn was inactive because its test was known to > be false, but with this change we needed to evaluate its test at runtime, so > we had to parse the insn itself, so we ran into problem #1. > > I have a patch to fix the __builtin_constant_p regression which I will be > checking in shortly.
Thanks for debugging and fixing this! - David